Prior to the advent of automatic machines for enabling one man to drive through the field picking up bales and arranging them into a stack on the bed of the machine, making a stack from the bales was a backbreaking, time-consuming process requiring the cooperation of several laborers. While such machines have thus filled a substantial need, they have suffered from many shortcomings, not the least of which is untoward complexity leading to reliability problems and high manufacturing costs. Furthermore, the stacks produced by many prior automatic machines have been so unstable as to require auxiliary props to keep the stacks from toppling over, such propping quite frequently being insufficient to achieve its intended purpose. This obviously complicates storage and handling, not to mention the monetary losses involved as a result of crop spoilage, etc.
Many of these problems in connection with prior machines are derived from the fact that they swing the various levels of the stack, or the stack itself in toto, through certain movements either during formation of the stack or during subsequent discharge thereof from the machine. In other words, instead of building a vertical stack and arranging the various bales of the stack in such a way that they cooperatively tie one another together, prior machines have relied upon various swinging "tables" and the like, which essentially add to the stack horizontally and subsequently require the stack to be upended in order to be discharged. Consequently, the bales are moved and shifted around to various locations during the stack-building process, and are never brought to their final positions in the stack until the stack has been unloaded from the machine. Thus, the weight of the various bales and the superimposed layers are not used to advantage in forming the stack and in tightly interlocking the bales as the stack is built. Even in those situations where the only upending of the stack occurs during discharge, quality stacks comparable to, if not better than, those achievable by hand are not obtained.